I cleaned my car on the weekend after a long winter and the last step was to check my fluid levels and oil. I probably haven't done this since November. I know, my bad. So I pop my hood and there is a rat's nest sitting on the engine It was a bit of straw, mostly foam insulation, and a ton of rat droppings. This makes sense because during the winter I would notice my fans sometimes had a bit of a dank/burning smell and I park outside near a garbage can. Now I know it was burning foam and rat smell. So I proceed to pull the nest out, vacuum the droppings, and carefully spray out what I could not get with the vacuum. I did a visual check and thankfully it looks like all the wires are intact.

On the drive to work today I noticed the smell was still there though. I tried to air it out and I turned my fans up to the max speed. On the top 3 fan speeds, there is a pretty loud whistling noise. Does anyone have an idea what's causing that? And any suggestions on how to get rid of rat smell?